AUTOMATED POLYMERASE CHAIN-REACTION PRODUCT SAMPLE PREPARATION FOR CAPILLARY ELECTROPHORESIS ANALYSIS

The analysis of crude polymerase chain reaction (PCR) products by capi llary electrophoresis (CE) is often compromised due to the presence of a high concentration of salt. Salt interferes with the electrokinetic injection and induces localized heating within the column; hence, PCR products must be desalted or cleaned-up prior to CE analysis. A varie ty of commercial clean-up systems are available that have been traditi onally used to prepare PCR products for cloning, sequencing and digest ion with restriction enzymes. These systems were tested for their effe ctiveness in preparing PCR products for CE analysis and were evaluated based on CE resolution, salt removal, DNA recovery, processing time a nd cost. One particularly effective clean-up system, membrane dialysis , was automated using a robotic workstation.